Example08_SpriteCollision.cpp

/*
  How to use CRM32Pro library. Example 8: Sprites collision.
  ---------------------------------------------------------
  
  >MegaStorm Systems (c) 2009
  >http://www.megastormsystems.com
  >Roberto Prieto
  
  - Initialize SDL and CRM32Pro.
  - Printing help on a window.
  - Use of log system.
  - Initialize graphics: window icon, video mode and cursor.
  - Load resources from DPF: images(IPF), fonts and sprite
  - Image following the mouse cursor.
  - Sprite smooth movement.
  - Using Fixed Logic Rate.
  - With F1 key, you can enable/disable collision system.
  - Information panel with FPS(real time) and number of collisions.
  - Exiting using right way ;)
  
 */

// ---Includes---
#include "CRM32Pro.h"
#ifdef _WINDOWS
 #include <windows.h>
#endif

// ---Defines---
#define EXAMPLE_VERSION "Example 8: Sprites Collision"
#define GFX_RESOURCE "data/gfx.dpf"     // DPF with graphic resources

// ---Prototypes---
void RenderGraphics(int);
void RenderGraphicsGL(int);
void PrintHelp();

// ---Global vars---
SDL_Surface *bg, *info, *backinfo, *surfCursor;
CRM32Pro_CFont *fInfo;
CRM32Pro_CSprite *sprRabbit;
SDL_Rect inf, rCursor;
Uint32 last = 0, lastinfo = 0;
Uint8 bFlagCollision = 1;

// -------------MAIN FUNCTION----------------
int main(int argc,char *argv[])
{
   Uint8       done = 0;
   int         DirX = 1, DirY = 1, SprX = 100, SprY = 100;
   SDL_Event   event;

   // -Print help on a window-
   PrintHelp();

   // -Log system initialize-    
   ILogSystem.Init("SpriteCollision.log",LOG_FILE,LOG_NORMAL,EXAMPLE_VERSION);

   // -CRM32Pro and SDL initialize-   
   if(CRM32Pro.Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO | SDL_INIT_TIMER) < 0)
   {
      ILogSystem.Msg(LOG_NORMAL," · [LOG] - Couldn´t initialize CRM32Pro: %s\n",SDL_GetError());        
      return 1;
   }    

   // -Desired config-
   CRM32Pro.Config.Title = EXAMPLE_VERSION;
   CRM32Pro.Config.Icon = IImage->Load(GFX_RESOURCE,"icono");
   CRM32Pro.Config.bMTFriendly = 1;
   //CRM32Pro.Config.VideoRenderer = RENDER_OPENGL;
   //CRM32Pro.Config.VideoAccel = ACCEL_HARDSMOOTH ;

   // -Graphics system initialize-  
   if(!CRM32Pro.SetVideoMode())
   {
      CRM32Pro.Quit();
      return 1;
   }

   // -Time system initialize-
   ITimeSystem->Init();
   ITimeSystem->SetRate(0,20);  // Optional: desired Rendering and Logic Frame Rate

   // -Set our render graphics function to fullfil desired Rendering Frame Rate-
   if(!CRM32Pro.IsGL()) CRM32Pro.SetRenderCallback(RenderGraphics);
   else CRM32Pro.SetRenderCallback(RenderGraphicsGL);

   // -Load resources: background, info panel, info font, sprite and image to follow the cursor-    
   bg = IImage->Load(GFX_RESOURCE,"background2");
   info = IImage->Load(GFX_RESOURCE,"info");
   inf.x = 6;inf.y = 6;inf.w = info->w;inf.h = info->h;
   backinfo = IImage->Load(GFX_RESOURCE,"info");        
   fInfo = new CRM32Pro_CFont();
   fInfo->Load(GFX_RESOURCE,"InfoFont");
   sprRabbit = new CRM32Pro_CSprite();
   sprRabbit->Load(GFX_RESOURCE,"rabbit");
   sprRabbit->AutoRestore(0);
   surfCursor = IImage->Load(GFX_RESOURCE,"Smiley");
   if(surfCursor == NULL) exit(1);
   rCursor.x = 100;rCursor.y = 110;rCursor.w = surfCursor->w;rCursor.h = surfCursor->h;

   // -Main loop-
   bFlagCollision = 1;
   done = 0;    
   while(!done)
   {            
                
      // 1.Logic frame stuff
          // Each logic frame (20 per seconds) we move the sprite. We assume that sprRabbit size is 64x64               
      SprX = SprX + (2 * DirX);
      SprY = SprY + (2 * DirY);
      if((SprX + 64) > CRM32Pro.screen->w) DirX = DirX * (-1);
      if((SprY + 64) > CRM32Pro.screen->h) DirY = DirY * (-1);
      if(SprX < 2) DirX = DirX * (-1);
      if(SprY < 2) DirY = DirY * (-1);
      sprRabbit->SetPosition(SprX,SprY,1);      
          
      // 2.Event loop: update all systems: graphics,events,timing...
      // surfCursor follow the position of mouse. With F1 activate/desactivate collision system. ESC exit.
      while(CRM32Pro.Update(&event))    
      {
         switch(event.type)
         {
            case SDL_KEYDOWN:
               if(event.key.keysym.sym == SDLK_ESCAPE) done = 1;
               if(event.key.keysym.sym == SDLK_F1) bFlagCollision = bFlagCollision * (-1);
                   break;
            case SDL_MOUSEMOTION:
               rCursor.x = event.motion.x - rCursor.w / 2;
               rCursor.y = event.motion.y - rCursor.h / 2;
               break;

            case SDL_QUIT:
               done = 1;
               break;
                        case EVENT_LOGICWAIT:
               // While CRM32Pro.Update() wait for fulfill the logic rate this event is raised  
                           // You could call to the Rendering Graphics here instead of to use the CRM32Pro callback.
                           break;
            default:
               break;
         }
      }
   }

   // -Free resources, show information and exit-
   delete fInfo;   
   sprRabbit->Info();
   delete sprRabbit;
    CRM32Pro.FreeSurface(bg);
   CRM32Pro.FreeSurface(info);
   CRM32Pro.FreeSurface(backinfo);
   CRM32Pro.FreeSurface(surfCursor);
   ITimeSystem->Info();
   CRM32Pro.VideoInfo();
   CRM32Pro.Quit();
   return 0;
}

// ---Our render graphics function---
void RenderGraphics(int bLogicUpdate)
{
   char  sTmp[16];
   int   isCollision = 0, nCollisions = 0;

   // Blit background
   SDL_BlitSurface(bg, NULL, CRM32Pro.screen, NULL);

   // Sprite blitting
   sprRabbit->Draw();

   // Detecting collisions
   nCollisions = 0;
   if(bFlagCollision == 1)
   {
      isCollision = sprRabbit->Collision(surfCursor,&rCursor,-1,-1,1);
      if(isCollision) nCollisions++;
   }
   // Image following the cursor blitting
   SDL_BlitSurface(surfCursor, NULL, CRM32Pro.screen, &rCursor);                                                        

   // Blit information panel: state of collision system and FPS (four times per second)
   SDL_BlitSurface(info,NULL,CRM32Pro.screen,&inf);     
   if((lastinfo + 250) < ITimeSystem->GetTime())
   {
      lastinfo = ITimeSystem->GetTime();
      // Restore original info panel
      SDL_BlitSurface(backinfo,NULL,info,NULL);

      // Are we detecting collisions?           
      if(bFlagCollision == 1) fInfo->PutString(info,62,7,"ON");
      else
         fInfo->PutString(info,62,7,"OFF");

      // Frames per second (real time)
      sprintf(sTmp,"%d",(Uint32)ITimeSystem->GetCurrentRFR());
      fInfo->PutString(info,43,23,sTmp);

      // Print number of collisions
      sprintf(sTmp,"%d",nCollisions);
      fInfo->PutString(info,70,42,sTmp);
   }
}

// ---Our render graphics function for OpenGL mode---
// In OpenGL modes, blitting from a surface to another surface requires some conversions
// so the best workaround is just blit everything to CRM32Pro.screen surface.
void RenderGraphicsGL(int bLogicUpdate)
{
   char  sTmp[16];
   int   isCollision = 0, nCollisions = 0;

   // Blit background
   SDL_BlitSurface(bg, NULL, CRM32Pro.screen, NULL);

   // Sprite blitting
   sprRabbit->Draw();

   // Detecting collisions
   nCollisions = 0;
   if(bFlagCollision == 1)
   {
      isCollision = sprRabbit->Collision(surfCursor,&rCursor,-1,-1,1);
          if(isCollision) nCollisions++;
   }

   // Image following the cursor blitting
   SDL_BlitSurface(surfCursor, NULL, CRM32Pro.screen, &rCursor);                                                        

   // Blit information panel: state of collision system and FPS (four times per second)
   lastinfo = ITimeSystem->GetTime();
   // Restore original info panel
   SDL_BlitSurface(backinfo,NULL,CRM32Pro.screen,&inf);

   // Are we detecting collisions?              
   if(bFlagCollision == 1) fInfo->PutString(CRM32Pro.screen,68,13,"ON");
   else   fInfo->PutString(CRM32Pro.screen,68,13,"OFF");

   // Frames per second (real time)
   sprintf(sTmp,"%d",(Uint32)ITimeSystem->GetCurrentRFR());
   fInfo->PutString(CRM32Pro.screen,49,29,sTmp);

   // Print number of collisions
   sprintf(sTmp,"%d",nCollisions);
   fInfo->PutString(CRM32Pro.screen,79,48,sTmp); 
}

// --------------------Help STUFF------------------------
// -Print help-
void PrintHelp()
{
        char *sMsg;

        // Create the message
        sMsg = new char[1024];
    strcpy(sMsg,"-----------------------------------------------------------\n");
        strcat(sMsg,"                     ");
        strcat(sMsg,EXAMPLE_VERSION);
        strcat(sMsg,"\n-----------------------------------------------------------\n\n");
        strcat(sMsg," Press [ESCAPE] key to exit.\n");
        strcat(sMsg," Press [F1] key to enable/disable collision detection.\n");
        strcat(sMsg,"\n To see further information, open 'SpriteCollision.log'.\n");
        strcat(sMsg,"\n");

        // Display the message
    #ifdef _WINDOWS
          MessageBox(NULL,sMsg,"CRM32Pro SDK - HelpScreen",MB_OK);
    #endif
        #ifdef _LINUX 
          printf("CRM32Pro SDK - HelpScreen\n%s",sMsg);
    #endif

        // Free the message
        delete sMsg;
}